A5091631955- Medical Imaging Techniques and Applications
- Advanced Radiotherapy Techniques
- Advanced X-ray and CT Imaging
- Radiation Therapy and Dosimetry
- Radiation Dose and Imaging
- Nuclear Physics and Applications
- Advanced MRI Techniques and Applications
- Lung Cancer Diagnosis and Treatment
- Medical Image Segmentation Techniques
- Radiation Detection and Scintillator Technologies
- Radiomics and Machine Learning in Medical Imaging
- Advanced X-ray Imaging Techniques
- Atomic and Subatomic Physics Research
- Digital Radiography and Breast Imaging
- Digital Image Processing Techniques
- Prostate Cancer Diagnosis and Treatment
- Advanced Vision and Imaging
- Photoacoustic and Ultrasonic Imaging
- Ultrasound Imaging and Elastography
- Particle Detector Development and Performance
- Electrical and Bioimpedance Tomography
- Lung Cancer Treatments and Mutations
- Hepatocellular Carcinoma Treatment and Prognosis
- Cardiac Imaging and Diagnostics
- Seismic Imaging and Inversion Techniques
Centre Léon Bérard
2015-2025
Centre de Recherche en Acquisition et Traitement de l'Image pour la Santé
2016-2025
Université Claude Bernard Lyon 1
2016-2025
Inserm
2016-2025
Centre National de la Recherche Scientifique
2016-2025
Institut National des Sciences Appliquées de Lyon
2014-2024
Canadian Nautical Research Society
2014-2023
Université Jean Monnet
2017-2019
Hospices Civils de Lyon
2014-2017
Lyon College
2016
EMPIRE10 (Evaluation of Methods for Pulmonary Image REgistration 2010) is a public platform fair and meaningful comparison registration algorithms which are applied to database intrapatient thoracic CT image pairs. Evaluation nonrigid techniques nontrivial task. This compounded by the fact that researchers typically test only on their own data, varies widely. For this reason, reliable assessment different has been virtually impossible in past. In work we present results launch phase...
We propose the Reconstruction Toolkit (RTK, http://www.openrtk.org), an open-source toolkit for fast cone-beam CT reconstruction, based on Insight (ITK) and using GPU code extracted from Plastimatch. RTK is developed by open consortium (see affiliations) under non-contaminating Apache 2.0 license. The quality of platform daily checked with regression tests in partnership Kitware, company supporting ITK. Several features are already available: Elekta, Varian IBA inputs, multi-threaded...
Purpose: Four‐dimensional computed tomography (4D CT) can provide patient‐specific motion information for radiotherapy planning and delivery. Motion estimation in 4D CT is challenging due to the reduced image quality presence of artifacts. We aim improve robustness deformable registration applied respiratory‐correlated imaging lungs, by using a global problem formulation pursuing restrictive parametrization spatiotemporal deformation model. Methods: A spatial transformation based on...
Respiratory motion causes artifacts in cone‐beam (CB) CT images acquired on slow rotating scanners integrated with linear accelerators. Respiration‐correlated CBCT has been proposed to correct for the respiratory but only a subset of CB projections is used reconstruct each frame 4D image and, therefore, adequate quality requires long acquisition times. In this article, authors develop an on‐the‐fly solution estimate and compensate reconstruction 3D from all projections. An priori model...
Purpose This work aims at investigating intensity corrected cone‐beam x‐ray computed tomography (CBCT) images for accurate dose calculation in adaptive modulated proton therapy (IMPT) prostate and head neck (H&N) cancer. A deformable image registration (DIR)‐based method a scatter correction approach using the data obtained from DIR as prior are characterized compared on basis of same clinical patient cohort first time. Methods Planning CT (pCT) daily CBCT (reconstructed measured...
Purpose: Proton CT (pCT) has the potential to accurately measure electron density map of tissues at low doses but spatial resolution is prohibitive if curved paths protons in matter not accounted for. The authors propose account for an estimate most likely path a filtered backprojection (FBP) reconstruction algorithm. Methods: energy loss first binned several proton radiographs different distances source exploit depth‐dependency path. This process named distance‐driven binning. A...
Exploiting the x-ray measurements obtained in different energy bins, spectral computed tomography (CT) has ability to recover 3-D description of a patient material basis. This may be achieved solving two subproblems, namely decomposition and tomographic reconstruction problems. In this work, we address projection images, which is nonlinear ill-posed problem.Our main contribution introduce material-dependent spatial regularization domain. The problem solved iteratively using Gauss-Newton...
Purpose: Deformable registration generally relies on the assumption that sought spatial transformation is smooth. Yet, breathing motion involves sliding of lung with respect to chest wall, causing a discontinuity in field, and smoothness can lead poor matching accuracy. In response, alternative methods have been proposed, several which rely prior segmentations. We propose an original method for automatically extracting particular segmentation, called mask, from CT image thorax. Methods: The...
Sliding motion is a challenge for deformable image registration because it leads to discontinuities in the sought deformation. In this paper, we present method handle sliding using multiple B-spline transforms. The proposed decomposes deformation into regions allow at their interfaces, but prevents unrealistic solutions by forcing those interfaces match. was evaluated on 16 lung cancer patients against single transform approach and multi transforms without constraint interface. target error...
Proton computed tomography (pCT) has been proposed as an alternative to x-ray (CT) for acquiring relative water stopping power (RSP) maps used proton treatment planning dose calculations. In parallel, it shown that dual energy CT (DECT) improves RSP accuracy when compared conventional single CT. This study aimed at directly comparing the of both modalities using phantoms scanned advanced prototype pCT scanner and a state-of-the-art DECT scanner.
Over the last decade, dual-energy CT scanners have gone from prototypes to clinically available machines, and spectral photon counting are following. They require a specific reconstruction process, consisting of two steps: material decomposition tomographic reconstruction. Image-based methods perform reconstruction, then decomposition, while projection-based first, As an alternative, 'one-step inversion' been proposed, which simultaneously. Unfortunately, one-step typically slower than their...
Currently, four-dimensional (4D) cone-beam computed tomography (CBCT) requires a 3-4 min full-fan scan to ensure usable image quality. Recent advancements in sparse-view 4D-CBCT reconstruction have opened the possibility reduce time and dose. The aim of this study is provide common framework for systematically evaluating algorithms from 1-min scan. Using framework, AAPM-sponsored SPARE Challenge was conducted 2018 identify compare state-of-the-art algorithms.A clinically realistic CBCT...
Respiratory motion is a major concern in cone-beam (CB) computed tomography (CT) of the thorax. It causes artifacts such as blur, streaks, and bands, particular when using slow-rotating scanners mounted on gantry linear accelerators. In this paper, we compare two approaches for motion-compensated CBCT reconstruction The first one analytic; it heuristically adapted from method Feldkamp, Davis, Kress (FDK). second algebraic: system equations generated new algorithm projection deformable...
We present a comprehensive analytical comparison of four types proton imaging set-ups and, to this end, develop mathematical framework calculate the width uncertainty envelope around most likely path depending on set-up geometry, detector properties, and beam parameters. As figure merit for spatial resolution achievable with each set-up, we use frequency at which modular transfer function density step decreases below 10%. verify results Monte Carlo simulations.
X-ray phase-contrast imaging (XPCI) is a family of techniques that makes contrast visible due to phase shifts in the sample. Phase-sensitive can potentially be several orders magnitude more sensitive than attenuation-based techniques, finding applications wide range fields, from biomedicine materials science. The accurate simulation XPCI allows for planning experiments, reducing need costly synchrotron beam access find suitable parameters. It also provide training data recently proposed...
Proton computed tomography (CT) has been described as a solution for imaging the proton stopping power of patient tissues, therefore reducing uncertainty conversion x-ray CT images to relative (RSP) maps and its associated margins. This study aimed investigate this assertion under assumption ideal detection systems. We have developed Monte Carlo framework assess performances main steps therapy treatment planning, i.e. or imaging, RSP based on calibration tissue phantom, dose simulations....
Purpose: Reconstruction of the beating heart in 3D + time catheter laboratory using only available C‐arm system would improve diagnosis, guidance, device sizing, and outcome control for intracardiac interventions, e.g., electrophysiology, valvular disease treatment, structural or congenital disease. To obtain such a reconstruction, patientˈs electrocardiogram (ECG) must be recorded during acquisition used reconstruction. In this paper, authors present 4D reconstruction method aiming to...
Four-dimensional cone-beam computed tomography (4D-CBCT) of the free-breathing thorax is a valuable tool in image-guided radiation therapy and upper abdomen. It allows determination position tumor throughout breathing cycle, while only its mean can be extracted from three-dimensional CBCT. The classical approaches are not fully satisfactory: respiration-correlated methods allow one to accurately locate high-contrast structures any frame, but contain strong streak artifacts unless acquisition...
Proton transmission imaging has been proposed and investigated as modality complementary to x-ray based techniques in proton beam therapy. In particular, it addresses the issue of range uncertainties due conversion an patient computed tomography (CT) image expressed Hounsfield Units (HU) relative stopping power (RSP) needed input treatment planning system. One approach exploit a single radiographic projection is perform patient-specific calibration CT RSP curve by optimising match between...
The state-of-the art for solving the nonlinear material decomposition problem in spectral computed tomography is based on variational methods, but these are computationally slow and critically depend particular choice of regularization functional. Convolutional neural networks have been proposed addressing issues. However, learning algorithms require large amounts experimental data sets. We propose a deep strategy U-Net architecture Sim2Real transfer approach where knowledge that we learn...